This application is for renewal of the Ruth L. Kirschstein National Research Service Award Postdoctoral Research Training Program (T32) in Pediatric Gastroenterology and Nutrition at the University of California, San Francisco (UCSF). The Program aims to train talented and dedicated young physicians to become independent and productive scientific investigators. These future scientists will research important health problems, focusing on the causes, pathogenesis, and treatment of digestive, liver and nutritional disorders in infants and children. Preference is given to trainees committed to a 4-year training program, including 3 years of research training in either Basic or Clinical/Translational Research mentored by established scientists. Basic research experience is supplemented with coursework, seminars, and inter-departmental retreats; trainees in clinical research often participate in the newly developed Training in Clinical Research Program that includes a 2-year Masters Degree in Clinical Research. Each trainee pursues an obligatory research project(s) supervised by experienced preceptors. Entry requirements include a MD degree and 3 years of residency in clinical pediatrics. Applicants with PhD degrees and defined career goals related to developmental gastroenterology or nutrition are also eligible. Administration of the program is restructured to take advantage of the strengthened Division of Pediatric Gastroenterology/Nutrition under the direction of Dr. Melvin Heyman. The quality of educational and research programs and activities will be closely monitored by trainee mentors, research preceptors, Internal Advisors, the Program Director, and periodic evaluations by External Advisors. Continuation of 3 training positions is requested. This Program is directly relevant to child health and development in training the next generation of scientists who will generate the advances essential for improving the quality of life and survival rates of children and adolescents with gastrointestinal, liver and nutrition-related disorders. Further, this training program represents an investment in the future of public health in general, as the multidisciplinary, intensive and innovative training provided by this Program will educate the leaders, teachers, and professional role models who will help determine the direction and contributions of American medicine domestically and throughout the world.